"Big four" accounting firm Deloitte suffered a breach last year that may have exposed 5 million internal emails as well as usernames and passwords, client information and health details, the Guardian reports.

The chairman of the U.S. Securities and Exchange Commission will face the Senate Banking Committee next week following the agency's belated disclosure that in May 2016, hackers stole secret market data from the SEC's systems and apparently used it for "illicit gain through trading."

Analyzing the impact of a breach of computers at the U.S. Securities and Exchange Commission leads the latest edition of the ISMG Security Report. Also, exploring alternative plans to implement cybersecurity regulations on credit reporting bureaus in the wake of the Equifax breach.

Canada had been lagging behind the U.S. and some other nations in terms of breach notification regulations, but now it's catching up, says attorney Imran Ahmad, who explains new regulations that are going into effect.

Hackers behind the mega-breach at Equifax stole data in May, but they - or other attackers - penetrated the credit bureau's systems in March, exploiting a vulnerability for which Apache Struts had issued a patch, just four days prior.

Equifax made an error that led to one of the largest and most sensitive data breaches of all time, and the mistake was elementary: The credit bureau failed to patch a vulnerability in Apache Struts - a web application development framework - in a timely manner.

Equifax has a new problem on its hands: Argentina. Investigators with security consultancy Hold Security discovered that Equifax's Argentina website exposed national identity numbers for at least 14,000 citizens. But the information exposure may be far more extensive.

What do you do if you're the CEO of a credit bureau that's suffered a massive breach, leading to Congressional probes, dozens of lawsuits, formal investigations by state attorneys general and calls for your resignation? Answer: Issue an apology via USA Today.

In the wake Equifax saying hackers may have stolen 143 million consumers' personal details, the company is already facing sharp questions over the robustness of its security defenses as well as reports that three executives sold stock after the breach was discovered, but before the news became public.

The Equifax breach revealed on Thursday is more significant that other mega-breaches because of the nature of the data that was potentially exposed, says cybersecurity attorney Imran Ahmad. He'll be a featured speaker at ISMG's Toronto Fraud & Breach Prevention Summit on Tuesday.

Credit reporting agency Equifax said Thursday a web application flaw exposed 143 million U.S. consumers' records to hackers, a startling breach from a company that ironically offers services to protect consumers from identity theft.

Instagram is warning that more users were affected by a hack of its systems than it first suspected. While email addresses - and some phone numbers - for celebrities, including Emma Watson and Lady Gaga, appear to have been compromised, 6 million account holders in total may have been affected.